I have a clicking noise coming from my rear end during deceleration. It is a Dana 44 with 3:73 gears. I replaced the clutches, spider gears, and carrier bearings. The drive shaft doesn't have excessive play and it still makes a clicking noise. What else could it be?

Did you ever drop the driveshaft to physically check the U-joints before replacing all those other parts? I just had a U-joint go south and there was no play. I did have what I would describe as pinging or clicking. Turns out a needle bearing had snapped in half. Always start with the components that are designed to wear out.